1. Field of the Invention
The present invention relates to a paper sheet processing apparatus and a paper sheet processing method that can reproduce an image printed on a paper sheet, such as, a banknote, a check, marketable securities, and a coupon.
2. Description of the Related Art
Banknote processing apparatuses that perform recognition processes such as denomination recognition and authentification based on a banknote image generated by scanning a banknote are known in the art. These banknote processing apparatuses recognize the banknotes based on the banknote images, and perform tasks such as calculating a total amount and sorting the banknotes by denomination, etc.
Paper sheet processing apparatuses that can process checks in addition to the banknotes have come to be used in recent times. When the processing target is the banknotes, these paper sheet processing apparatuses perform the recognition processes, such as, denomination recognition and authentification, a counting process for determining denomination-wise number of banknotes and a total amount, a process for sorting and stacking banknotes according to the type of the banknotes, such as, denomination, and a process for reading out serial numbers printed on the banknotes. In contrast, when the processing target is the checks, the paper sheet processing apparatuses perform tasks such as a process for reading out information, such as, a check amount, and a process for generating and saving images of the checks. The image of the check can be used when a problem arises while processing the check or to reconfirm the contents of the check, such as, the amount or an account number.
Unlike in the case of the banknotes, when receiving from customers and processing the checks, marketable securities, and coupons, if the paper sheet image is stored and thereby the information printed on the paper sheet is preserved, the original paper sheet can either be returned to the customer or destroyed without safekeeping the original paper sheet. Hence, there is a demand for a paper sheet processing apparatus that can generate and archive the image of the paper sheet while recognizing the type of the paper sheet or reading out the information printed on the paper sheet.
Because a sensor is used in the conventional banknote processing apparatus to generate the banknote image that is used in the recognition process, this apparatus can also be used as the paper sheet processing apparatus also handling paper sheets other than banknotes. However, there is a difference in a degree of resolution required for the image to be used for the type recognition process and that required for the image to be used for post processing, such as, confirmation of the information relating to the paper sheet. Specifically, the image to be used for post processing from which the printed information has to be read out needs to be of a higher resolution compared to the image to be used for the type recognition process for which it is enough to extract a feature required for recognizing the type of the paper sheet.
To be able to generate images of different resolutions using the same sensor, one approach could be to first generate a high resolution image, and thereafter convert the high resolution image into a lower resolution image. However, there is a disadvantage in this approach that the process of converting the resolution of the image is time consuming.
The recognition process is performed by comparing features between the generated image of the paper sheet and a template image pre-installed for each paper sheet. If a high resolution image generated for post processing can be used for the recognition process at the same resolution, there will be no need to change the resolution of the image. However, to realize this, the current low-resolution template images will need to be generated in high resolution. Moreover, if the recognition process is customized for a low-resolution template image, the recognition process also would need to be altered to suit the high-resolution template image.
Hence, there is a requirement for a paper sheet processing apparatus that can generate a high resolution image required for the post processing while simultaneously generating a low resolution image required for the type recognition process as in the conventional apparatus.